When the power goes out in Austin, Texas, it doesn’t always happen at a convenient time. A summer outage can mean hours without air conditioning, while a winter storm can leave homeowners wondering how long the refrigerator, water heater, and other essential systems will continue operating.
That’s one reason standby generators have become such an important consideration for homeowners who want more dependable backup power. But before buying a generator, there’s a question that needs to be answered first:
How big of a generator do I need?
The answer isn’t necessarily the biggest generator you can afford. In fact, choosing an oversized generator can be just as problematic as choosing one that doesn’t have enough capacity.
The right generator should be sized around the electrical equipment you actually want to operate during an outage. That may mean keeping only the essentials running, or it could mean powering nearly everything in the house.
Understanding that difference can make the generator selection process much easier.
Start by Deciding What You Want to Power
The first step in choosing a standby generator is figuring out what you expect it to do when the utility power goes down.
There are generally two approaches: essential-load backup and whole-home backup.
With essential-load backup, the generator supplies power to the circuits and appliances that matter most. These might include:
- Refrigerators and freezers
- A gas furnace or HVAC system
- Selected lighting
- Internet equipment
- Security systems
- Medical equipment
- Sump pumps
- Garage doors
- A water heater
- Other important household circuits
This approach can reduce the size and cost of the generator because you’re not trying to operate every electrical appliance simultaneously.
Whole-home backup takes a different approach. Instead of deciding which circuits should receive backup power, the generator is sized to handle a much larger portion of the home’s electrical demand.
For some Austin homeowners, that convenience is worth the additional investment. For others, a carefully planned essential-load system makes more sense.
There’s no universal answer. It depends on the home, the electrical system, the appliances, and how the homeowner wants to live during an outage.
Don’t Forget About Your HVAC System
For many Austin homeowners, air conditioning is one of the biggest factors in generator sizing.
That makes sense. Austin summers can be brutally hot, and losing power during a heat wave is more than an inconvenience. Maintaining a comfortable indoor temperature may be a major priority, particularly for households with young children, older adults, or pets.
Central air conditioners can have significant electrical requirements, especially when the compressor starts.
This is where generator sizing becomes more complicated than simply adding up the numbers printed on appliances.
An HVAC system may have a relatively manageable running load but require considerably more power for a short period when the compressor starts. If the generator can’t handle that temporary demand, the system may struggle to start or the generator could become overloaded.
Modern generator systems and HVAC equipment can sometimes use technologies such as soft-start devices to reduce startup demand. Whether one makes sense for a particular home depends on the equipment and electrical system.
A professional evaluation can help determine the actual requirements instead of relying on guesswork.
Refrigerators and Freezers Still Matter
A refrigerator doesn’t consume electricity at the same rate all day.
The compressor cycles on and off, meaning the running load can be relatively modest while the startup demand is higher.
For a homeowner planning essential-load backup, refrigerators and freezers are usually among the first appliances worth considering. Keeping food cold during a prolonged outage can prevent hundreds of dollars in spoiled groceries.
If your home has multiple refrigerators, a separate freezer, or other refrigeration equipment, those loads should be included in the generator calculation.
What About an Electric Water Heater?
Water heaters can have a substantial impact on generator sizing.
An electric tank-style water heater uses heating elements that can draw a significant amount of power while operating. Depending on the size and configuration of the water heater, it may represent one of the larger electrical loads in the house.
That’s important when deciding whether you want your generator to operate the water heater during an outage.
Some homeowners may decide hot water is an essential service and include it in the backup plan. Others may prefer to temporarily turn off the water heater so more generator capacity is available for air conditioning and other priorities.
Tankless electric water heaters can also have substantial electrical requirements, so they shouldn’t be overlooked when planning backup power.
Electric Ranges Can Add a Significant Load
An electric range is another appliance that can influence generator sizing.
If you have an electric oven and cooktop, using several burners and the oven at the same time can create a considerably larger electrical demand than simply keeping the refrigerator running.
That doesn’t necessarily mean you need a massive generator.
The important question is how the electrical loads are expected to operate together.
For example, a homeowner may be comfortable avoiding heavy cooking during an outage while prioritizing air conditioning, refrigeration, lighting, and other essentials. Another homeowner may want normal access to the kitchen regardless of whether utility power is available.
Your generator should reflect those expectations.
Pool Equipment Can Change the Calculation
Swimming pools are a major consideration for many Austin-area homeowners.
Pool pumps, variable-speed pumps, heaters, lighting, automation systems, and other equipment all have electrical requirements. A pool pump may also have a startup demand that needs to be considered.
If you want the pool equipment to operate during a power outage, it needs to be included in the generator load calculation.
But ask yourself whether every pool-related system truly needs to run when the grid is down.
Some homeowners may only want the pump and essential equipment operating. Others may want their entire pool system backed up.
Pool heaters deserve particular attention because some systems can require substantial amounts of electricity.
What About an EV Charger?
Electric vehicles are becoming increasingly common in Austin, and an EV charger can be one of the largest electrical loads in a modern home.
A Level 2 EV charger can draw significantly more power than many traditional household appliances. If you plan to charge your vehicle while the generator is also running the air conditioner, water heater, range, refrigerator, and other equipment, the total demand can increase quickly.
This doesn’t automatically mean an EV charger can’t be connected to a backup system.
Instead, it means the charger needs to be part of the planning process.
Some homeowners may choose not to charge their vehicle during an outage. Others may want enough generator capacity to continue charging.
The right choice depends on how you use your EV and what you consider essential during a power failure.
Running Loads vs. Starting Loads
One of the biggest misunderstandings homeowners have about generator sizing is the difference between running watts and starting watts.
Running load is the amount of electricity equipment generally needs while operating.
Starting load is the temporary surge that some motors require when they initially turn on.
Air conditioners, refrigerators, freezers, pumps, and other motor-driven equipment can have higher startup requirements than their normal running consumption.
Imagine that several appliances are already running when the air conditioner suddenly kicks on. The generator has to be capable of handling that additional demand.
This is why simply adding the running wattage listed on appliances doesn’t always provide an accurate generator size.
A proper generator load calculation takes these situations into account.
How Generator Load Calculations Work
Generator sizing isn’t supposed to be a guessing game.
A qualified electrician can evaluate the home’s electrical service, major appliances, equipment ratings, and anticipated usage to determine the electrical demand that the backup system needs to support.
The calculation may consider:
- Electrical service size
- HVAC equipment
- Refrigeration
- Water heating
- Cooking appliances
- Pool equipment
- EV charging
- Lighting
- Pumps
- Other major electrical loads
- Motor startup requirements
- Which loads are expected to operate simultaneously
The goal isn’t necessarily to calculate the absolute maximum amount of electricity every appliance could consume at the exact same moment.
Instead, the generator should be selected based on realistic electrical requirements and the way the homeowner intends to use the system.
This is one reason professional generator installation is valuable. An experienced electrician can look at the entire electrical system rather than simply recommending a generator based on the square footage of the house.
Why the Biggest Generator Isn’t Necessarily the Best Generator
It can be tempting to think that bigger is always better.
If a 14-kilowatt generator can power some of your home’s appliances, why not buy a 26-kilowatt or 30-kilowatt model instead?
There are several reasons that may not be the best approach.
A larger generator generally represents a larger upfront investment. Depending on the installation, it may also involve additional electrical equipment, fuel considerations, space requirements, and installation costs.
There’s also no benefit to paying for capacity you don’t actually need.
The better strategy is to determine your actual electrical requirements first and then select equipment that provides appropriate capacity.
In other words, size the generator around the house rather than sizing the house around the generator.
Can a Handy Homeowner Install a Standby Generator?
This is where generator installation differs from many ordinary home improvement projects.
A homeowner who is comfortable with tools may be able to handle plenty of DIY projects around the house. Installing a standby generator, however, involves considerably more than setting the equipment on a concrete pad and connecting a few wires.
A permanent standby generator typically involves electrical connections, transfer equipment, grounding and bonding considerations, fuel connections, clearances, permitting, and coordination with the home’s existing electrical system.
Errors in the installation can create serious safety hazards or leave the backup system unable to operate properly when it’s needed.
That’s why this type of work is generally best left to qualified professionals.
Texas homeowners should also understand that electrical work is subject to state and local requirements, and the specific permitting and licensing requirements can depend on the work being performed and the jurisdiction where the property is located.
For homeowners who aren’t licensed electricians, attempting a permanent generator installation themselves can create unnecessary safety and compliance risks.
The goal isn’t simply to get the generator running. The goal is to have a backup power system that operates safely and reliably when the utility power fails.
Choosing a Professional Generator Installer in Austin
A standby generator is an investment in your home’s resilience. It’s worth taking the time to have the electrical requirements evaluated before purchasing equipment.
An experienced Austin electrician can inspect the home’s existing electrical system, discuss which appliances and systems the homeowner wants to back up, calculate anticipated loads, and help determine an appropriate generator size.
Homeowners in Austin, Texas can work with Tejas Electric for a reliable backup generator installation service.
Tejas Electric understands that no two homes have exactly the same electrical demands. A smaller home with gas appliances may have very different backup power requirements than a larger Austin home with multiple HVAC systems, electric water heating, a pool, and an EV charger.
The generator should be selected based on those real-world differences.
A professional installation can also help ensure the generator, transfer equipment, and electrical connections work together as intended.
Think About Your Future Electrical Needs
Generator sizing shouldn’t only consider what your home uses today.
Think about what you may add over the next several years.
Are you planning to purchase an electric vehicle? Add a pool? Install another HVAC system? Convert from gas appliances to electric? Build an addition? Add a detached garage or workshop?
Those changes can significantly affect the home’s electrical demand.
If you’re already considering one of these upgrades, mention it during the generator planning process. It may be possible to account for future electrical needs when designing the backup system.
Planning ahead can prevent you from discovering later that the generator you installed isn’t capable of supporting the equipment you’ve added.
The Right Generator Starts With the Right Questions
There’s no single generator size that is perfect for every Austin home.
The right size depends on what you want to keep operating during an outage, how those systems interact, and how much electrical demand your home can place on the generator at one time.
Start by asking yourself:
What absolutely needs to keep running?
Then consider your HVAC system, refrigerators, freezers, water heater, cooking equipment, pool equipment, EV charger, lighting, and other major electrical loads.
Most importantly, don’t overlook starting loads. The amount of electricity an appliance needs to start can be very different from what it uses once it’s running.
A professional load calculation can take all of these factors into consideration.
Tejas Electric can help Austin, Texas-area homeowners evaluate their electrical needs and plan a standby generator installation based on the actual demands of the property.
The best generator isn’t necessarily the biggest one sitting on a showroom floor. It’s the one that’s properly sized for your home, your priorities, and the way you expect to use backup power when the lights go out.
